This is an application from the Center for Hearing and Balance at Johns Hopkins University School of Medicine for a Research Core Grant from the NIDCD. The Center includes eleven investigators drawn from the departments of Otolaryngology- Head and Neck Surgery, and Biomedical Engineering. These laboratories provide a Research Base of nine R01 awards with scientific aims ranging from the molecular biophysics of hair cells to behavioral assays of hearing and balance. Three Research Cores are proposed that will facilitate ongoing research and stimulate new initiatives at the interface between existing programs. The Molecular Biology Core will provide training for and access to molecular genetic research tools including quantitative polymerase chain reaction and generation and assessment of molecular probes for in situ hybridization and immunohistology. A 'real-time' fluorescent monitor thermal cycler will be available through this Core. The Histology Core will provide technical assistance and material support for light and electron microscopic studies. Users will receive guidance in tissue preparation, sectioning, and visualization techniques. Fluorescence microscopy and a digital imaging station will be available through the Core. The Engineering Core will develop and distribute advanced data acquisition and signal analysis software, and provide general hardware and software support for Center laboratories. An Administrative unit will oversee operations throughout the Cores, design and maintain a central Website, provide clerical and personnel support and prepare reports.